We present a framework for analyzing privacy and anonymity in social networks and develop a new re-identification algorithm targeting anonymized social-network graphs. To demonstrate its effectiveness on real-world networks, we show that a third of the users who can be verified to have accounts on both Twitter, a popular microblogging service, and Flickr, an online photo-sharing site, can be re-identified in the anonymous Twitter graph with only a 12% error rate.

Basically, the researchers are saying that anonymized data isn't really anonymous -- and social networks that insist they're "safe" because they've anonymized the data are being somewhat disingenuous.

Reader Comments

Re: Isn't that difficult

It's more than that though.

What they found was that people tend to have the same groups of friends, even when they're "anonymous", and that by analyzing the groups of friends on different social sites combined with a few other tell tale signs, you can narrow down who they are 2 out of 3 times.

I should have published on this years ago cause I've hunted people down in this manner for ages. It's not that difficult but it does require patience and some ability to use logic, as well as a keen understanding of human nature. Each piece of information is a new stepping stone to the next and eventually yields the ultimate goal.